"""Manage LLDP."""

# Copyright (C) 2013 Nippon Telegraph and Telephone Corporation.
# Copyright (C) 2015 Brad Cowie, Christopher Lorier and Joe Stringer.
# Copyright (C) 2015 Research and Education Advanced Network New Zealand Ltd.
# Copyright (C) 2015--2019 The Contributors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


from collections import defaultdict

from faucet import valve_util
from faucet import valve_of
from faucet import valve_packet
from faucet.valve_manager_base import ValveManagerBase


class ValveLLDPManager(ValveManagerBase):
    """Manage LLDP."""

    def __init__(
        self,
        vlan_table,
        highest_priority,
        logger,
        notify,
        inc_var,
        set_var,
        set_port_var,
        stack_manager,
    ):
        self.vlan_table = vlan_table
        self.highest_priority = highest_priority
        self.logger = logger
        self.notify = notify
        self._set_var = set_var
        self._inc_var = inc_var
        self._set_port_var = set_port_var
        self.stack_manager = stack_manager

    def _lldp_match(self, port):
        return self.vlan_table.match(
            in_port=port.number,
            eth_dst=valve_packet.LLDP_MAC_NEAREST_BRIDGE,
            eth_dst_mask=valve_packet.BRIDGE_GROUP_MASK,
            eth_type=valve_of.ether.ETH_TYPE_LLDP,
        )

    def add_port(self, port):
        ofmsgs = []
        if port.receive_lldp:
            ofmsgs.append(
                self.vlan_table.flowcontroller(
                    match=self._lldp_match(port),
                    priority=self.highest_priority,
                    max_len=128,
                )
            )
        return ofmsgs

    def del_port(self, port):
        ofmsgs = []
        if port.receive_lldp:
            ofmsgs.append(
                self.vlan_table.flowdel(
                    match=self._lldp_match(port), priority=self.highest_priority
                )
            )
        return ofmsgs

    def verify_lldp(
        self,
        port,
        now,
        valve,
        other_valves,
        remote_dp_id,
        remote_dp_name,
        remote_port_id,
        remote_port_state,
    ):
        """
        Verify correct LLDP cabling, then update port to next state

        Args:
            port (Port): Port that received the LLDP
            now (float): Current time
            other_valves (list): Other valves in the topology
            remote_dp_id (int): Received LLDP remote DP ID
            remote_dp_name (str): Received LLDP remote DP name
            remote_port_id (int): Recevied LLDP port ID
            remote_port_state (int): Received LLDP port state
        Returns:
            dict: Ofmsgs by valve
        """
        if not port.stack:
            return {}
        remote_dp = port.stack["dp"]
        remote_port = port.stack["port"]
        stack_correct = True
        self._inc_var("stack_probes_received")
        if (
            remote_dp_id != remote_dp.dp_id
            or remote_dp_name != remote_dp.name
            or remote_port_id != remote_port.number
        ):
            self.logger.error(
                "Stack %s cabling incorrect, expected %s:%s:%u, actual %s:%s:%u"
                % (
                    port,
                    valve_util.dpid_log(remote_dp.dp_id),
                    remote_dp.name,
                    remote_port.number,
                    valve_util.dpid_log(remote_dp_id),
                    remote_dp_name,
                    remote_port_id,
                )
            )
            stack_correct = False
            self._inc_var("stack_cabling_errors")
        port.dyn_stack_probe_info = {
            "last_seen_lldp_time": now,
            "stack_correct": stack_correct,
            "remote_dp_id": remote_dp_id,
            "remote_dp_name": remote_dp_name,
            "remote_port_id": remote_port_id,
            "remote_port_state": remote_port_state,
        }
        return self.update_stack_link_state([port], now, valve, other_valves)

    def update_stack_link_state(self, ports, now, valve, other_valves):
        """
        Update the stack link states of the set of provided stack ports

        Args:
            ports (list): List of stack ports to update the state of
            now (float): Current time
            valve (Valve): Valve that owns this LLDPManager instance
            other_valves (list): List of other valves
        Returns:
            dict: ofmsgs by valve
        """
        stack_changes = 0
        ofmsgs_by_valve = defaultdict(list)
        stacked_valves = set()
        if self.stack_manager:
            stacked_valves = {valve}.union(
                self.stack_manager.stacked_valves(other_valves)
            )
        for port in ports:
            before_state = port.stack_state()
            after_state, reason = port.stack_port_update(now)
            if before_state != after_state:
                self._set_port_var("port_stack_state", after_state, port)
                self._inc_var(
                    "port_stack_state_change_count",
                    labels=valve.dp.port_labels(port.number),
                )
                self.notify(
                    {"STACK_STATE": {"port": port.number, "state": after_state}}
                )
                self.logger.info(
                    "Stack %s state %s (previous state %s): %s"
                    % (
                        port,
                        port.stack_state_name(after_state),
                        port.stack_state_name(before_state),
                        reason,
                    )
                )
                stack_changes += 1
                port_up = False
                if port.is_stack_up():
                    port_up = True
                elif port.is_stack_init() and port.stack["port"].is_stack_up():
                    port_up = True
                for stack_valve in stacked_valves:
                    stack_valve.stack_manager.update_stack_topo(port_up, valve.dp, port)
        if stack_changes or valve.stale_root:
            self.logger.info(
                "%u stack ports changed state, stale root %s"
                % (stack_changes, valve.stale_root)
            )
            valve.stale_root = False
            notify_dps = {}
            for stack_valve in stacked_valves:
                if not stack_valve.dp.dyn_running:
                    continue
                ofmsgs_by_valve[stack_valve].extend(
                    stack_valve.add_vlans(stack_valve.dp.vlans.values())
                )
                for port in stack_valve.dp.stack_ports():
                    ofmsgs_by_valve[stack_valve].extend(
                        stack_valve.switch_manager.del_port(port)
                    )
                ofmsgs_by_valve[stack_valve].extend(
                    stack_valve.stack_manager.add_tunnel_acls()
                )
                path_port = stack_valve.stack_manager.chosen_towards_port
                path_port_number = path_port.number if path_port else 0.0
                self._set_var(
                    "dp_root_hop_port",
                    path_port_number,
                    labels=stack_valve.dp.base_prom_labels(),
                )
                notify_dps.setdefault(stack_valve.dp.name, {})[
                    "root_hop_port"
                ] = path_port_number
            # Find the first valve with a valid stack and trigger notification.
            for stack_valve in stacked_valves:
                if stack_valve.dp.stack.graph:
                    self.notify(
                        {
                            "STACK_TOPO_CHANGE": {
                                "stack_root": stack_valve.dp.stack.root_name,
                                "graph": stack_valve.dp.stack.get_node_link_data(),
                                "dps": notify_dps,
                            }
                        }
                    )
                    break
        return ofmsgs_by_valve
